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The Compose strong skipping mode does not fix the stability issue with Kotlin collections. Here’s a post on the main things to watch out for when using them 👇 open.substack.com/pub/effectiv...

open.substack.comStrong skipping does not fix Kotlin collections in Jetpack Compose ⚠️Things to watch out for when using List, Map, Set, etc

Saurabh Arora

@saurabharora.bsky.social

1 Mar 2025

"Referential equality returns true if the List reference is the same; it does not care about its content" Is this true? I need to try this out myself. Your post & Google's official post say different things Their post says it calls equals on every item in the list. medium.com/androiddevel...

Jorge Castillo

@jorgecastillo.dev

It’s a different thing. That post mentions that adding it to the “whitelist” configuration file is same as flagging it as Stable, so two instances of it are compared using equals. Strong skipping does not do that, collections remain unstable and compared with ===.

1/3/25, 10:16 pm0 reposts0 likes

Saurabh Arora

@saurabharora.bsky.social

1 Mar 2025

Ah I see I see. So both are right in their own way. Might be good to have that in your post?

Jorge Castillo

@jorgecastillo.dev

1 Mar 2025

Yeah definitely. I can see people can get confused. Will update it.

Ben Trengrove

@bentrengrove.dev

1 Mar 2025

So the idea is with strong skipping, === is an extremely fast check. Imagine you have a lazy list and an array with a couple of hundred items, 3 on screen. Depending on the cost of equals, it's faster to let that higher level recomposition happen with ===.

Ben Trengrove

@bentrengrove.dev

1 Mar 2025

Then the lazy list calls equals on the 3 visible items. If your list was stable, you'd call equals on each item and pay it for a couple of hundred times. Then the lazy list still calls equals again for the 3 visible items. Tldr, stable lists aren't always faster even if they avoid recomposition